645570443 has 12 divisors (see below), whose sum is σ = 775196352. Its totient is φ = 535494960.

The previous prime is 645570439. The next prime is 645570449. The reversal of 645570443 is 344075546.

It is a happy number.

It is not a de Polignac number, because 645570443 - 2² = 645570439 is a prime.

It is a super-2 number, since 2×645570443² = 833522393750432498, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 645570397 and 645570406.

It is not an unprimeable number, because it can be changed into a prime (645570449) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 210980 + ... + 214017.

It is an arithmetic number, because the mean of its divisors is an integer number (64599696).

Almost surely, 2^645570443 is an apocalyptic number.

645570443 is a deficient number, since it is larger than the sum of its proper divisors (129625909).

645570443 is a wasteful number, since it uses less digits than its factorization.

645570443 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 425042 (or 425035 counting only the distinct ones).

The product of its (nonzero) digits is 201600, while the sum is 38.

The square root of 645570443 is about 25408.0783019889. The cubic root of 645570443 is about 864.2668977647.

The spelling of 645570443 in words is "six hundred forty-five million, five hundred seventy thousand, four hundred forty-three".